chore(Cargo.toml): remove a duplicated dev-dependency

Signed-off-by: ADD-SP <add_sp@outlook.com>

Author: ADD-SP

Cargo.toml

@@ -49,7 +49,6 @@ tokio = { version = "1", features = ["rt-multi-thread", "net", "macros", "signal
 hyper = { version = "1.3.1", features = ["server", "http1"] }
 hyper-util = { version = "0.1.3", features = ["tokio"] }
 http-body-util = "0.1.1"
-prometheus-client-derive = { path = "./prometheus-client-derive" }
 
 [build-dependencies]
 prost-build = { version = "0.12.0", optional = true }